DESCRIPTION (adapted from the application): Mass Spectrometry became an important fixture of the research landscape at Vanderbilt University in 1968 when Dr. J. Throck Watson joined the faculty and initiated studies using stable isotopes in Clinical Pharmacology. In 1983 Dr. Ian A. Blair was recruited to reestablish mass spectrometry as a core facility for the university. In January 1997, Dr. Blair left Vanderbilt to take a faculty position at the University of Pennsylvania. Dr. Lawrence J. Marnett assumed administrative responsibility for the mass spectrometry facility on an interim basis until a permanent Director could be recruited. In February 1998, Dr. Richard M. Caprioli joined the faculty in the Department of Biochemistry and he initiated steps to reorganize and renovate the facilities, acquire new personnel and instruments. The former mass spectrometry resources have been restructured as the Vanderbilt University Mass Spectrometry Research Center (VU-MSRC), as described below. In May 1998, Dr. David L. Hachey joined the Vanderbilt Pharmacology faculty and assumed daily management of the shared instrument facility. Dr. Caprioli is currently recruiting students, postdoctoral fellows and staff for his research program, while Dr. Hachey is recruiting additional staff to rebuild the shared instrument program. The VU-MSRC currently (August 1998) has nine staff members, of whom seven are involved with the shared instrument facility. Renovations and recruitment of new staff will be complete by the spring of 1999. The MSRC is located on the 8th floor of Medical Research Building I (MRBI). The Mass Spectrometry Core facility has seven mass spectrometers and three HPLC systems, and the mass spectrometry research facility has four additional instruments. Structural analysis can be accomplished on any of the mass spectrometers. However, the three triple quadrupole instruments are especially adept at structural determination using tandem MS/MS techniques and collision-induced dissociation. Routine quantitative assays are most economically performed by HPLC systems equipped with UV or electrochemical detectors. However, when more difficult analytical assays arise, mass spectrometry affords better selectivity and sensitivity than simple HPLC, often with femtomole or picomole detection limits. Furthermore, when structural or quantitative problems demand the very highest performance, new high sensitivity microanalytical techniques are available in Dr. Caprioli's laboratory on either a time-of-flight or an ion trap mass spectrometer equipped with a nanoelectrospray ionization source that afford attomole to femtomole sensitivity. The Mass Spectrometry Core is part of the Vanderbilt University Mass Spectrometry Research Center (MSRC) located in the Medical School. The MSRC consists of a core mass spectrometry service laboratory directed by Dr. Hachey and the research laboratories of Dr. Caprioli. In addition to providing routine analytical and mass spectrometric services via the core facilities, CNRU investigators can form collaborations with Dr. Caprioli to solve analytical and structural problems that require non-routine, cutting edge technology. As newer techniques become better understood, they are made available to the user community through the core service laboratory. Thus, the MS Core satisfies the routine analytical needs of CNRU investigators, and also makes available new analytical capabilities for research problems demanding more innovative solutions that are beyond the scope of a service laboratory.